Method to refrigerate a jacket for keeping a transplant cold

ABSTRACT

A jacket (10) for keeping a transplant (46) cold during the time the transplant in surgical way is connected to a receiver comprises a wall (12, 14) with a cavity (22) containing a frozen liquid, which melts under absorption of heat from the transplant. Before the transplant is placed in the jacket (10), the liquid, e.g. water, is frozen by being subjected to vacuum, vapour released from the liquid being absorbed by a substance, e.g. zeolite.

BACKGROUND OF THE INVENTION

The invention generally relates to a method for refrigerating a jacket,and, more specifically, to a method of using a refrigerated jacket toenclose and keep a transplant cold during the time the transplant issurgically installed within a recipient's body.

U.S. Pat. No. 5,014,695, discloses a jacket, which prevents atransplant, such as a kidney, from being heated, and thereby destroyed,by the body heat of the transplant recipient during the time it takes toconnect the transplant surgically in the body of the recipient.

The known jacket is kept cold by a liquid the liquid, is circulatedthrough the jacket via tubes connected to an outside source supplyingcold liquid to the circulation. However with this jacket the tubes canobstruct access to the surgical site, and therefore impede thetransplant procedure.

SUMMARY OF THE INVENTION

An object of the invention is to bring about a method of casting atransplant which makes it possible to enclose the transplant by a jackethaving no tubes and ensuring that the transplant keeps an even anddesired temperature during the time the transplant organ is surgicallyconnected to the receiver.

According to the method the present invention, a jacket, which comprisesa wall with a cavity containing a liquid and showing an opening to thecavity, is placed in a compartment. The compartment is evacuated so thatthe cavity is evacuated through the opening and the liquid within thecavity freezes.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of a jacket with an apparatus to evacuate a cavity of thejacket for carrying through the method according to the invention isdescribed below with reference to the enclosed drawing figures, wherein:

FIG. 1 in a sectional view shows the jacket in the apparatus forevacuating and thereby refrigerating the jacket and

FIG. 2 in a sectional view shows a transplant enclosed by the jacket andready to be surgically connected to a receiving patient.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

With reference to the drawing figures, a jacket 10 consisting of twohalves 12 and 14, respectively, which are turnably connected to eachother around an axis 16, is illustrated. Each respective half includesan inner, rigid shell 18, e.g. of stainless steel, and an outer, rigidshell 20, e.g. of plastic. The shells 18,20 cooperate to define a cavity22 therebetween which communicates with the surrounding atmosphere viaan opening 24 in the outer shell 20. A liquid absorbing body 26 isdisposed within the cavity 22 and kept in contact with the inner shell18 by a perforated element 28. Each respective body 26 has been suppliedwith a determined quantity of liquid through the opening 24.

When the jacket 10 is to be refrigerated, the jacket is placed on aperforated upper surface 29 of a circular-cylindrical container 30containing a substance 32 absorbing vapor from the liquid. The container30 rests at its circumference on a plate 34, so a space 37 is definedbetween a lower perforated surface 36 of the container 30 and the plate.The space 37, communicates with a vacuum pump 38 via a conduit 40. Ahood 42 is placed over the jacket and the container on the plate 34. Thepump 38 is started, the respective cavity 22 being evacuated via theopening 24 and the substance 32. At a certain low pressure of themagnitude of 250-4000 Pa, which is readable on a manometer 44, theliquid in the body 26 begins to evaporate under heat rejection from theliquid, which thereby freezes, after which the pump 38 is stopped andsurrounding air is let into the hood 42, so that it can be lifted offand make the jacket 10 available. It would require much energy and takelong time for the vacuum pump 38 to pump away the vapour of the liquid.Therefore the container 30 with the substance 32 is arranged to absorbthe vapour.

The transplant, e.g. a kidney 46, which shall be connected to arecipient and which is furnished in a cooled state, is now placed in thejacket 10 which is folded together around the transplant, as is shown inFIG. 2. The inner shells 18 have a form fitting to the shape of thetransplant. The original, determined quantity of liquid in the bodies 26is so large, that the liquid which has frozen in the bodies 26 will meltunder absorption of heat via the shells 18 from the transplant at aconstant temperature during the time it takes to surgically connect thetransplant to the recipient.

The liquid can consist of water and the substance 32 of zeolite. Byadding different substances to the water, different melting temperaturescan be obtained.

It shall be pointed out that the principle made use of at the inventionto freeze a liquid, e.g. water, by subjecting it to vacuum and therebyletting the vapour released from the liquid be absorbed by a substance,e.g. zeolite, is known per se through U.S. Pat. No. 5,207,073.

The jacket 10 is supplied containing said determined quantity of liquidin a sterile package, the respective opening 24 being sealed by a pieceof tape 48, which is removed before the cavity 22 shall be evacuated.The piece of tape 48 is again brought over the opening 24, before thetransplant shall be connected to the receiver.

The transplant can consist of another organ than a kidney, e.g. a heart,a lung or a liver.

We claim:
 1. Method for refrigerating a jacket (10), said jacket beingused to enclose and keep a transplant (46) cold while the transplant issurgically connected to a recipient, said jacket (10) having a wall witha cavity (22) containing a liquid and an opening (24) to the cavity,comprising the steps of placing the jacket in a compartment which isevacuated, evacuating the cavity through the opening and freezing theliquid.
 2. Method according to claim 1, wherein vapor, which isliberated from the liquid during the evacuation, is absorbed by asubstance (32) located in the compartment.